GB /T 889.1 (GB) and ISO 7040 (ISO) are equivalent fastener standards that specify the same or very similar products. Both standards cover 10 fastener types in our database.
GB /T 889.1 (GB standard) and ISO 7040 (ISO standard) are equivalent standards that define the same fastener geometry and mechanical requirements. Minor differences may exist in tolerances, marking requirements, or referenced test methods, but the products are interchangeable in most applications. Always verify specific project requirements with your engineer.
| Property | GB /T 889.1 | ISO 7040 |
|---|---|---|
| Standard Body | GB | ISO |
| Product Types | 10 fastener types | |
| Interchangeable? | Yes — equivalent standard | |
From: Prevailing Torque Type Hexagon Regular Nuts (with Non-Metallic Insert) - Property Classes 5, 8 and 10 — applies to both GB /T 889.1 and ISO 7040
| Size | P | e | r | k_max | k_min | s_max | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|---|---|---|
| M10 | 3.5 | 45 | 46 | 50.85 | 32.6 | 32.40 | 30.00 | 24.3 | 19.44 | 42.75 | 30.1 |
| M12 | 4 | 53.8 | 55 |
Both GB /T 889.1 and ISO 7040 fasteners are available with various surface treatments. Common options for these standards include:
Request detailed technical specifications, material certifications, and availability information for your application requirements. Our engineering team can provide product recommendations, custom specifications, and technical documentation.
| ✓ |
| Prevailing Torque Type Hexagon Nuts (with non-metallic insert), Style 1 | ✓ |
| Prevailing Torque Type Hexagon Nuts,(With Non-Metallic Insert) Style 1. Property Classes 5, 8 and 10 | ✓ |
| Prevailing Torque Type Hexagon Regular Nuts(With Non-Metallic Insert)-Property Classes 5,8 And 10 | ✓ |
| Prevailing Torque Type Hexagon Thick Nuts with Non-Metallic Insert | ✓ |
| 60.79 |
| 38.9 |
| 38.90 |
| 36.00 |
| 29.4 |
| 23.52 |
| 51.11 |
| 36.4 |
| M3 | 0.7 | 6.78 | 7 | 7.66 | 6.00 | 4.60 | 4.00 | 2.9 | 2.32 | 5.88 | 5.52 |
| M4 | 1 | 9.78 | 10 | 11.05 | 8.00 | 6.75 | 6.00 | 4.9 | 3.92 | 8.88 | 7.42 |
| M5 | 1.5 | 15.73 | 16 | 17.77 | 11.9 | 10.80 | 10.00 | 8.04 | 6.43 | 14.63 | 11.2 |
| M6 | 2 | 20.67 | 21 | 23.36 | 17.00 | 15.10 | 14.00 | 12.1 | 9.68 | 19.64 | 15.9 |
| M8 | 2.5 | 29.16 | 30 | 32.95 | 22.8 | 21.60 | 20.00 | 16.9 | 13.52 | 27.70 | 20.7 |
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